Background video and audio out of sync

I am having trouble with my background menus. When I set my backgrounds as use clip from conversion then a time and set audio the same my backgrounds on the completed conversion are out of sync. Does anyone know what I might be doing wrong. Hardware on my PC is AMD quad core and 8gb of ram on an asus m4n78 pro board. So I dont think its a resource issue. I think I’m making an error in my settings just not sure where.